Non-invasive prenatal diagnosis of down syndrome: a dream come true

Abstract

Our group discovered the presence of cell-free fetal DNA in plasma of pregnant women. This finding offered opportunities for the development of non-invasive approaches for prenatal diagnosis. However, fetal DNA co-exists with a large background of maternal DNA and amounts to just some 10% of the total DNA in maternal plasma. Despite the technical challenges, we developed an approach based on massively parallel sequencing for the non-invasive detection of fetal Down syndrome by detecting the small increments in chromosome 21 DNA sequences in maternal plasma. We showed in a study of 750 pregnancies that Down syndrome can be accurately identified by direct analysis of maternal plasma DNA. The method could be further adapted for the prenatal detection of trisomy 18 and trisomy 13. A number of groups have since confirmed our findings. Non-invasive prenatal detection of fetal Down syndrome has since been implemented as a routine service at a number of centres around the world. <h3>Acknowledgement</h3> Supported by the University Grants Committee of the Government of the Hong Kong Special Administrative Region, China, under the Areas of Excellence Scheme (AoE/M-04/ 06), the General Research Fund Scheme of the Hong Kong Research Grants Council (CUHK463109), and an Innovation and Technology Fund (ITS/054/09).